Automatic shut-off valve



May 17,1927. 11,628,675

L. D. LovEKlN AUTOMATIC SHUT-OFF VALVE 'Filed July 21. 1925 Patented May17, 1927.

LUTHER D. LOVEKIN, F WYNNEWOOD, PENNSYLVANIA.

AUTOMAATIC SHUT-OFF VALVE.

Application filed July 21,v

My invention relates to automatic shut off valves intended for use infuel conduits and operating to close and shut off the'tlow of fiuid fuelwhere for any reason the tem# perature exceeds a determined amount. Theobjects which I have in view are to provide a. device of the kindindicated in which the valve will close with an abrupt movement when thecritical temperature is reachedand also to provide a construction whichwill have the minimum resistance t`0 valve closing from friction and atthe same time be free from liability to leakage of the `fluid fuel.

In my construction I make luse of an abutment of fusible metal as ameans of holding the valve in open position and a leading feature of myinvention consists in employing a stop of fusible metal in the form of aplate extending inthe path of the plunger which holds the valve open andforan open space lying also in the path of the plunger so that when theplunger has fractured or perforated the plate it will be free to move inthe open space until the valve with which it is connected'is seated. lBypreference I form the plate of fusible metal in the form of a disksupported at its edges and extend.- ing over an open space which whenthe disk is in place forms a closed chamber so that the air containedinthis chamber cannot escape.- By preference also I form in the rear sideof the disk an annular groove surrounding the portion of the plateagainst which the plun er abuts and which I have found will faci itatethe breaking through of the plunger when the critical temperature4 isreached.

Another important feature of my invention consists 1n the constructivefeatures hereinafter described by means of which the movement of thevalve and plunger can occur without resistance from friction while atthe Sametime' the escape of the fluid fuel is etfectually prevented.

Reference being now had to the drawing v .which illustrates m invention,and whic4 shows a sectional e evation of a valve embodying myimprovement. v

1A indicates the valve casing forming 'a part of a conduit vfor duidfuel, either gas or l oil.' Ais th'e .valve seat in the casing; A athreaded passageformed through the casing. yA. is an externally threadedannulus 1n and v:forming a part of thefstiiliing box.

into whichV screws "is an internally 1925. serial No, 44,9e4.

threaded passage formed through the casing, 'the cover indicated at B. Cis .the valve, from which, as shown, extends the plunger indicated atC1. D is a spring acting to press the valve C toward its seat. E is aguide tube for the plunger C1, formed with a threaded end which screwsinto `the threaded opening A2 and with an annular seat El at its outerend. F is a stuffing box ring screwing on the threaded annulus A3 andacting on the split gland as indicatedv at F1; G indicating the stuffingin the stuffing box H is a fitting screwing on the threaded portion A ofthe casing and having as shown a threaded end Hl adapted to be screwedinto the hot water container. ln the fitting H and close to the portionof this fitting which screws into the hot water container I form achamber H2 around the edge of which is formed the seat H3 for thefusil-ile metal disk and the seat H4, against which the annular seat Elof the tube E tits and makes a tight joint. I is a disk of fusible metalfitting on the seat H3, and preferably formed as indicated with anannular groove I3 on its rear face.. i In operation the fusible Ametalplate of whatever form it maybe desired to use, is placed in the seatrovided for it yand the plunger C1 abutte against the plate as shown soas to keep the valve C open. The tubular guide is then screwed out untilits annular bearing E1 forms a tight joint with a permanent seat H4. Thepressure exerted on the screw threads will for most purposes, form atight joint to prevent the escape of gas or oil, but for greaterprecaution I prefer toA employ a stuffing box as shown and described,which will etfectually 'prevent the escape of gas from the casing aroundthe tube E, while of course the escape of as from the inside of the tubeis revented the seating of its annular seat 1.

When the temperature to which the fusible metal plate I lor i -isexposed exceeds a determined amount, the resistin power'of the fusiblemetal is so impaired .t at the action of the spring D through theplunger Cl will break orperforate the plate, permitting a quick closingaction of the valve. The cham.- ber lying beneath the fusible plateInust of course be 'of such dimensions as to permit the free movement'ofthe plunger after the supporting plate has broken or become perforated.When my safety appliance is used in connection with a hot Watercontainer I have found it advisable that the chamber over which thefusible plate extends be of such a character as to be entirely closed bythe lplate, so that any air contained in it will ecome heated'\'to thetemperature of the surrounding metal.

Having now `described my invention, what I claim as new and desire tosecure by Letters Patent, is:

A1. In combination with a valve casing adapted to be located (in aconduit for fluid fuel, a valve, means tending to seat said valve, aplunger extending from the valve through the Wall of the casing, a guidetube for the plunger screwing into the wall of valve, a plungerextending from the valveA the casing and extending beyond the same, saidtube having an annular seat formed at its outer end, a support for -afusible stop and an abutment against which the annular seat on the tubecan be screwed. and a fusible stop for the plunger located to hold thevalve open.

2. In combination with a `valve casing adapted to be located in aconduit for fluid fuel, a valve, means tending to seat said through theWall of the casing, a guide tube for the plunger screwing into the wallof the casing and extending beyond the same, said tube having an annularseat formed at its outer end, a stuling box located on the outside cithe casing and surrounding the guide tube, a support for a fusible stopand an abutment against which the annular seat on the tube can bescrewed, and a fusible stop for the plunger located to hold the valveopen.

3. In combination with a valve easing adapted to be located in a conduitfor fluid fuel` a valve. means tending to seat said valve, a pungerextending from the valve through the wall of the casing` a guide tubefor the plunger screwing into the wall of the casing and extendingbeyond the saine` said tube having anv annular Seat formed at its outerend, a support for a fusible stop and an abutment against which theannular seat on the tube can be screwed, and a fusible plate extendingover an opening located in the path of the plunger. said plate acting asa stop for the plunger.y

LUTHER iD. LOVEKIN.

